TW202412132A - Testing apparatus and testing method - Google Patents

Abstract

A testing apparatus for testing a testing target device, wherein: the testing target device is formed on a testing target body, and is a backside-illumination type imaging device which light is input into from a backside, which is the surface on the reverse side thereof from a side provided with a wiring layer; the testing apparatus comprises a placement stand that supports the testing target body while facing the backside of the imaging device; the placement stand has a transparent placement surface that the testing target body is placed on, and a radiation unit that is disposed below the placement surface and that radiates light toward the testing target body placed on the placement surface; the radiation unit has a light-guiding plate having a facing surface that faces the testing target body while sandwiching the placement surface between the light-guiding plate and the testing target body, and a light source unit that is provided to a region laterally outside from the light-guiding plate and that emits light toward a lateral edge surface of the light-guiding plate; the light-guiding plate emits light that is emitted from the light source unit and input from the lateral edge surface of the light-guiding plate toward the placement surface from the facing surface; the placement surface further has an optical member that transmits light approaching the testing target body placed on the placement surface from the facing surface of the light-guiding plate; and the optical member is subdivided into a plurality of regions, with the light transmittance being configured variably per each of the regions.

Description

Inspection device and inspection method

The present disclosure relates to an inspection device and an inspection method.

The inspection device of Patent Document 1 inspects the photographic element by allowing light to enter the photographic element formed on the inspected object while allowing the contact terminal to electrically contact the wiring layer of the photographic element. In Patent Document 1, the photographic element allows light to enter from the inner surface, and the inner surface is a surface opposite to a side provided with the wiring layer. The inspection device of Patent Document 1 comprises: a mounting table on which the inspected object is mounted in a state opposite to the inner surface of the photographic element and formed of a light-transmitting component; and a light irradiation mechanism, which is arranged opposite to the inspected object with the mounting table in between and has a plurality of LEDs facing the inspected object.

Patent document 1: Japanese Patent Application Publication No. 2019-106491

The technology related to the present disclosure is to use a side-incident type irradiation unit in the inspection of an internally illuminated imaging element, so that a uniform planar light within the surface can be irradiated onto the inspection object.

The present invention discloses an inspection device for inspecting an inspection object element. The inspection object element is an internal illumination type photographic element that allows light to enter from the inner surface, and is formed on the inspection object. The inner surface is a surface opposite to a side provided with a wiring layer. The inspection device is provided with a mounting table that supports the inspection object in a shape opposite to the inner surface of the photographic element. The mounting table has: a transparent mounting surface for mounting the inspection object; and an irradiation unit that is arranged below the mounting surface and irradiates light toward the inspection object mounted on the mounting surface; the irradiation unit has: a guide The light plate has an opposite surface that is opposite to the inspection object with the mounting surface in between; and the light source part is arranged in an area on the outer side of the light guide plate and emits light toward the side end surface of the light guide plate; the light guide plate allows the light emitted from the light source part and injected from the side end surface of the light guide plate to be emitted from the opposite surface toward the mounting surface; the mounting table further has an optical component, and the optical component allows the light from the opposite surface of the light guide plate to pass through toward the inspection object mounted on the mounting surface; the optical component is configured to be divided into a plurality of areas and the transmittance can be changed for each of the areas.

According to the present disclosure, when a side-incident type irradiation unit is used in the inspection of an internally illuminated imaging element, it is possible to irradiate the inspection object with planar light that is uniform within the surface.

In the semiconductor manufacturing process, a plurality of semiconductor elements having a predetermined circuit pattern are formed on a substrate such as a semiconductor wafer (hereinafter referred to as a "wafer"). The formed semiconductor elements are inspected for electrical characteristics and the like, and are screened into good and bad products. For example, the semiconductor elements are inspected using an inspection device such as a probe tester in the state of the substrate before each semiconductor element is separated.

In the inspection device, a probe card is arranged above a stage supporting a substrate. The probe card is a probe having multiple needle-shaped contact terminals. During inspection, the probe card and the wafer on the stage are brought close to each other so that each probe of the probe card contacts each electrode of the semiconductor element formed on the substrate. In this state, an electrical signal is supplied to the semiconductor element through each probe from a test head arranged on the upper part of the probe card. Then, the semiconductor element is screened to see if it is defective based on the electrical signal received from the semiconductor element by the test head through each probe.

When the semiconductor device to be inspected is a photographic device such as a CMOS sensor, unlike other general semiconductor devices, the inspection is performed while irradiating the photographic device with light. In recent years, as a photographic device, an internally illuminated photographic device has been developed that receives light incident from the inner side opposite to the surface side where the wiring layer is formed.

In the inspection device for the internal surface illumination type imaging element, the mounting table supports the substrate in a state facing the internal surface of the imaging element. In addition, in the inspection device for the internal surface illumination type imaging element, the mounting table has: a transparent mounting surface for mounting the substrate; and an irradiation unit, which is arranged below the mounting surface and irradiates light toward the substrate mounted on the mounting surface.

The irradiation part, for example, includes: a light guide plate having an opposing surface that is opposite to the substrate with the mounting surface in between; and a light source part that is disposed in an area on the outer side of the light guide plate and emits light toward the side end surface of the light guide plate. Furthermore, in the irradiation part, the light guide plate reflects the light emitted from the light source part and incident from the side end surface of the light guide plate toward the opposing surface by a reflection point or the like, and emits the light from the opposing surface as a planar light. Then, the planar light is irradiated onto the substrate placed on the mounting surface. In addition, hereinafter, the irradiation part in which the light is incident from the side end surface of the light guide plate is referred to as a side-incident type irradiation part.

Furthermore, when the substrate is irradiated with planar light during inspection, the planar light is preferably uniform within the surface. When a side-incident irradiation unit is used, as a method for making the planar light uniform within the surface, a method of adjusting the intensity of the light incident on the side surface of the light guide plate, a method of adjusting the size or arrangement of the reflection points of the light guide plate, etc. can be considered. However, in such methods, it is difficult to guide the planar light to be uniform within the surface, that is, it is difficult to make the planar light uniform within the surface.

Therefore, the technology related to the present disclosure is to use a side-incident type irradiation unit in the inspection of an internally illuminated imaging element, so that a uniform planar light within the surface can be irradiated onto the inspection object.

Hereinafter, the inspection device and the inspection method related to the present embodiment will be described with reference to the drawings. In addition, in the present specification and drawings, the same symbols will be given to the elements having substantially the same functional configuration to omit repeated description.

In the technology related to this embodiment, since the inspection target element is an internal surface illumination type imaging element, the internal surface illumination type imaging element will be described first.

[Internal Surface Illumination Type Photographic Element] FIG. 1 is a top view schematically showing the structure of a substrate as an inspection object on which an internal surface illumination type photographic element is formed, and FIG. 2 is a cross-sectional view schematically showing the structure of the internal surface illumination type photographic element. As shown in FIG. 1 , a plurality of internal surface illumination type photographic elements D are formed on a substantially circular plate-shaped wafer W as an example of a substrate.

The internally illuminated imaging element D is a solid-state imaging element, and has a photoelectric conversion unit PD which is a photodiode and a wiring layer PL including a plurality of wirings PLa, as shown in FIG. 2 . In addition, in the internally illuminated imaging element D, light is incident from a side (the inner side of the wafer W) opposite to a side (the surface side) where the wiring layer PL is provided. Then, the internally illuminated imaging element D receives the light incident from the inner side of the wafer W through the on-chip lens L and the color filter F with the photoelectric conversion unit PD. The color filter F is composed of a red color filter FR, a blue color filter FB, and a green color filter FG.

In addition, an electrode E is formed on the surface Da of the internal illumination type imaging device D, that is, the surface of the wafer W, and the electrode E is electrically connected to the wiring PLa of the wiring layer PL. The wiring PLa is used to input an electrical signal to the circuit element inside the internal illumination type imaging device D, or to output an electrical signal from the circuit element to the outside of the internal illumination type imaging device D. The wiring layer PL may also include a pixel transistor that controls a signal related to the photoelectric conversion unit.

[Inspection device] Next, the inspection device related to this embodiment is described. Fig. 3 and Fig. 4 are respectively a perspective view and a front view showing the schematic structure of the needle tester 1 as the inspection device related to this embodiment. In Fig. 4, in order to show the components built into the storage chamber and the loader of the needle tester 1 of Fig. 3, a part of them is shown in cross section.

The probe tester 1 is used to inspect the electrical characteristics of a plurality of internally illuminated imaging devices D (hereinafter sometimes abbreviated as imaging devices D) formed on a wafer W. As shown in FIGS. 3 and 4 , the probe tester 1 includes a storage chamber 2, a loader 3 disposed adjacent to the storage chamber 2, and a tester 4 disposed to cover the storage chamber 2.

The storage chamber 2 is a hollow frame, and has a stage 10 as a mounting table. As described later, the stage 10 supports the wafer W in a manner such that the inner surface of the imaging element D faces the stage 10.

In addition, the stage 10 is configured to be movable in the horizontal direction and the vertical direction, and can adjust the relative position of the probe card 11 and the wafer W so that the electrode E on the surface of the wafer W contacts the probe 11 a of the probe card 11 .

In addition, a probe card 11 is arranged above the pedestal 10 in the storage chamber 2 so as to face the pedestal 10. The probe card 11 has a plurality of needle-shaped probes 11a as contact terminals. Each probe 11a is formed to be able to contact a corresponding electrode E on the surface of the wafer W. The probe card 11 is connected to the tester 4 through the interface 12. When inspecting the imaging element D, each probe 11a contacts the corresponding electrode E, supplies the power input from the tester 4 through the interface 12 to the imaging element D, or transmits the signal from the imaging element D to the tester 4 through the interface 12.

The sensor bridge 30 and the advancing and retreating mechanism 33 disposed in the storage chamber 2 will be described later.

The loader 3 takes out the wafer W stored in a FOUP (not shown) as a transport container and transfers it to the stage 10 of the storage chamber 2. In addition, the loader 3 receives the wafer W after the electrical characteristics of the imaging element D have been inspected from the stage 10 and stores it in the FOUP.

The loader 3 has a control unit 13 that performs various controls. The control unit 13 is composed of a computer having a processor such as a CPU or a memory, and has a program storage unit. The program storage unit stores a program for controlling the operation of each component of the probe tester 1 during the electrical characteristic inspection or the illumination distribution acquisition process described later. The above program also performs the calculations required for the electrical characteristic inspection or the illumination distribution acquisition process. In addition, the above program can be recorded in a computer-readable storage medium, or it can be installed from the storage medium to the control unit 13. The above storage medium can be a temporary storage or a non-transient storage.

The control unit 13 is connected to the stand 10 via the wiring 14 and is connected to the tester computer 16 via the wiring 15. The control unit 13 controls the operation of the light source unit 52 of the stand 10 described later based on the input signal from the tester computer 16. The control unit 13 may also be provided in the storage chamber 2.

The tester 4 has a test board (not shown) that reproduces a part of the circuit configuration of the motherboard on which the imaging element D is mounted. The test board is connected to the tester computer 16. The tester computer 16 determines whether the imaging element D is good or not based on the signal from the imaging element D. In the tester 4, by replacing the above-mentioned test board, the circuit configuration of various motherboards can be reproduced.

In addition, the probe tester 1 has a user interface portion 17. The user interface portion 17 is used to display information to the user or allow the user to input instructions, and is composed of, for example, a display panel having a touch panel or a keyboard.

In the probe tester 1 having the above-mentioned parts, when checking the electrical characteristics of the imaging device D, the tester computer 16 transmits data to the test board connected to the imaging device D via the probes 11a. Then, the tester computer 16 determines whether the transmitted data has been correctly processed by the test board based on the electrical signal from the test board.

[Internal structure of storage chamber 2] Next, the internal structure of storage chamber 2 will be further described using FIG. 5. FIG. 5 is a three-dimensional diagram showing a schematic internal structure of storage chamber 2.

As shown in the figure, in the storage room 2, the pedestal 10 is arranged on the base 20, and has an X-direction moving unit 21 that moves along the X direction in the figure, a Y-direction moving unit 22 that moves along the Y direction in the figure, and a Z-direction moving unit 23 that moves along the Z direction in the figure. The X-direction moving unit 21, the Y-direction moving unit 22, and the Z-direction moving unit 23 constitute a moving mechanism that enables the pedestal 10 and the illumination sensor 32 described later to move relative to each other.

The X-direction moving unit 21 moves the pedestal 10 in the X-direction along the guide rail 21a extending in the X-direction by rotating the ball screw 21b. The ball screw 21b is rotated by a motor (not shown). In addition, the movement amount of the pedestal 10 can be detected by an encoder (not shown) combined with the motor.

The Y-direction moving unit 22 moves the pedestal 10 in the Y direction along the guide rail 22a extending in the Y direction by rotating the ball screw 22b. The ball screw 22b is rotated by the motor 22c. In addition, the encoder 22d combined with the motor 22c can detect the movement amount of the pedestal 10.

With the above configuration, the X-direction moving unit 21 and the Y-direction moving unit 22 enable the pedestal 10 to move in the X-direction and the Y-direction that are orthogonal to each other along the horizontal plane.

The Z-direction moving unit 23 has a motor and an encoder (not shown), and moves the stage 10 up and down along the Z direction, and can detect the amount of movement. The Z-direction moving unit 23 moves the stage 10 toward the probe card 11 so that the electrode of the imaging element D formed on the wafer W abuts against the probe. In addition, the stage 10 is configured to be able to rotate freely around the θ direction in the figure on the Z-direction moving unit 23 by a motor (not shown).

In addition, a lower camera unit 24 is disposed inside the storage chamber 2. The lower camera unit 24 photographs the probe 11a formed on the probe card 11. The lower camera unit 24 has a lower camera (not shown) composed of, for example, a CMOS (Complementary Metal Oxide Semiconductor) camera and an optical system (not shown) that guides light from the photographed object to the lower camera. The lower camera unit 24 photographs the probe 11a formed on the probe card 11 by the lower camera, and the photographing result is output to the control unit 13, for example, for alignment of the electrode on the wafer W and the probe 11a. The lower camera unit 24 is fixed to the stage 10 and moves in the X direction, Y direction, and Z direction together with the stage 10.

Furthermore, a sensor bridge 30 as a mounting portion is disposed in the interior of the storage chamber 2 at a position between the base 10 and the probe card 11 in the vertical direction. The sensor bridge 30 is provided with an upper camera 31 as a photographing portion and an illuminance sensor 32 as an illuminance measuring portion.

The upper camera 31 is used to photograph the wafer W and is composed of, for example, a CMOS camera. The upper camera 31 can also be provided with an optical system similar to the lower camera. The illuminance sensor 32 is used to obtain the in-plane distribution of the illuminance of light from the mounting surface 40a (refer to the symbol 40a in FIG. 6 described later) of the wafer W in the pedestal 10. The illuminance sensor 32 measures the illuminance of light from a local area of the mounting surface. In addition, in the following description, it is assumed that the area on the mounting surface where the illuminance sensor 32 measures the illuminance in one measurement (hereinafter referred to as the "unit sensor area") is the area corresponding to one imaging element D.

The shooting result of the upper camera 31 or the measurement result of the illuminance sensor 32 is output to the control unit 13 .

The sensor bridge 30 is provided with an advance and retreat mechanism 33 (see FIG. 4 ). The advance and retreat mechanism 33 has a guide rail 33a that guides the advance and retreat of the sensor bridge 30 and a driving part 33b, and the driving part 33b is composed of a combination of a motor and a ball screw that drives the sensor bridge 30 to move along the guide rail 33a. The advance and retreat mechanism 33 advances and retreats the sensor bridge 30, that is, the illuminance sensor 32 relative to the area opposite to the mounting surface of the pedestal 10. Specifically, the advance and retreat mechanism 33 moves the illuminance sensor 32 between an area outside the mounting surface of the pedestal 10 in a plan view and a predetermined area opposite to the mounting surface.

[Base 10] Next, the structure of the base 10 will be described. FIG6 is a cross-sectional view schematically showing the structure of the base 10. FIG7 is a partially enlarged cross-sectional view of a liquid crystal panel described later.

The pedestal 10 supports the wafer W in a configuration in which the inner surface of the imaging element D faces the pedestal 10 , and as shown in FIG. 6 , includes a top plate 40 , an irradiation unit 40 , a liquid crystal panel 60 , and a base 70 .

The top plate 40 is a flat plate-shaped member made of a light-transmitting material, and its upper surface 40a serves as a mounting surface for mounting the wafer W. The top plate 40 diffuses and transmits the light emitted from the irradiation unit 50 toward the wafer W and passing through the liquid crystal panel 60. That is, the top plate 40 is formed to function as a diffusion plate, for example. In addition, the top plate 40 is formed in a square shape, for example, with one side having a length greater than the diameter of the wafer W when viewed from above.

The “light-transmitting material” mentioned above is a material that allows light of a wavelength within the inspection range (ie, light from the irradiation unit 50 ) to pass therethrough, such as glass.

The irradiation unit 50 is placed below the mounting surface of the pedestal 10, and irradiates light toward the wafer W placed on the mounting surface. In this example, the irradiation unit 50 is arranged below the top plate 40 whose top surface 40a serves as the mounting surface, and irradiates light toward the wafer W placed on the top surface 40a. In addition, hereinafter, the top surface 40a of the top plate 40 may be referred to as the mounting surface 40a.

The irradiation unit 50 includes, for example, a light guide plate 51 and a light source unit 52 .

The light guide plate 51 has an opposing surface 51a that is opposite to the wafer W with the mounting surface 40a in between, and is, for example, a member formed in the shape of a flat plate. The shape and size of the light guide plate 51 when viewed from above are, for example, the same as those of the top plate 40. The light guide plate 51 reflects and diffuses the light emitted from the light source unit 52 and incident from the side surface of the light guide plate 51 inside, and emits it from the opposing surface 51a as planar light. In addition, the light guide plate 51 is configured so that, when viewed from above, the imaging element formation area of the wafer W is included in the area where the planar light is emitted.

The light source unit 52 is disposed in an area outside the side of the light guide plate 51, and emits light toward the side end surface of the light guide plate 51. The light source unit 52 has, for example, a plurality of LEDs (not shown) disposed along each side of the light guide plate 51. In addition, in the present embodiment, in order to release the heat of the LED of the light source unit 52 to the outside of the base 10, a heat sink 53 is disposed on the inner surface of the substrate (not shown) supporting the LED. The heat sink 53 is formed of, for example, a metal material. A path through which a refrigerant such as water for cooling the LED of the light source unit 52 can flow can also be formed on the heat sink 53.

The liquid crystal panel 60 is an example of an optical component that allows light from the above-mentioned opposite surface 51a of the light guide plate 51 to pass through the wafer W placed on the placing surface 40a, and is configured to be divided into a plurality of regions, and the transmittance can be changed for each of the regions (hereinafter referred to as the element region). Specifically, as shown in FIG. 7, for example, the liquid crystal panel 60 has a liquid crystal layer 61 and glass substrates 62, 63 that sandwich and seal the liquid crystal layer 61, and polarizing plates 64, 65 are provided on the portions of the glass substrates 62, 63 on the opposite sides of the liquid crystal layer 61. In addition, in the liquid crystal panel 60, transparent electrodes (not shown) are formed on the glass substrates 62, 63 in each of the above-mentioned element regions. By changing the voltage applied between the transparent electrodes according to each element region, the transmittance of each element region can be adjusted. A circuit (not shown) including a power source for applying a voltage to the transparent electrode is controlled by the control unit 13. That is, the light transmittance of the liquid crystal panel 60 is controlled by the control unit 13.

In the probe 1, the light emitted from the LED of the light source section 52 of the irradiation section 50 and incident from the side surface of the light guide plate 51 is reflected and diffused inside the light guide plate 51, and is emitted as planar light from the opposite surface 51a opposite to the wafer W. Then, the planar light, for example, passes through the liquid crystal panel 60 and the top plate 40, and is incident on the imaging element D of the wafer W. In addition, the LED of the light source section 52 emits light including the wavelength of the inspection range. The wavelength of the inspection range is, for example, light of the wavelength in the visible light region, and depending on the type of the imaging element D, it may be light outside the visible light region such as infrared rays.

The base 70 is disposed at a position opposite to the wafer W on the mounting surface 40a, that is, below the light guide plate 51, with the top plate 30, the liquid crystal panel 60, and the light guide plate 51 in between, and supports the top plate 40, the liquid crystal panel 60, and the irradiation unit 50. For example, the top plate 40 is held on the liquid crystal panel 60 by bonding with a transparent bonding material, the liquid crystal panel 60 is held on the irradiation unit 50 by bonding with a transparent bonding material, and the irradiation unit 50 is held on the base 70 by bonding with a bonding material.

The base 70 may also be provided with a temperature control unit (not shown) that adjusts the temperature of the imaging element D of the wafer W placed on the placement surface 40a. The temperature control unit may also be provided with at least one of a heater that heats the wafer W (e.g., a resistance heating heater) or a device that cools the wafer W (e.g., a flow path for a cooling medium).

[Illuminance distribution acquisition/transmittance determination processing] Next, the illuminance distribution acquisition/transmittance determination processing performed by the probe tester 1 is described. The illuminance distribution acquisition/transmittance determination processing is a process for acquiring the in-plane distribution of the illuminance of the light irradiated through the mounting surface 40a of the pedestal 10 and determining the transmittance of the liquid crystal panel 60. For example, it is performed when the probe tester 1 is started or maintained, or during quality control (QC: Quality Control).

In the illumination distribution acquisition/transmittance determination process, first, the pedestal 10 is moved to a predetermined position in the horizontal plane and a predetermined height by the X-direction moving unit 21, the Y-direction moving unit 22, and the Z-direction moving unit 23. In addition, the predetermined position is, for example, a position corresponding to one of the plurality of imaging elements formed on the wafer W, that is, a position corresponding to a unit sensor area of the mounting surface 40a. Simultaneously with the movement of the pedestal 10 or before or after the movement, the sensor bridge 30 is moved by the advance and retreat mechanism 33 so that the sensor bridge 30 is located in the area above the moved pedestal 10.

Next, when the liquid crystal panel 60 (each component area) is adjusted to a predetermined transmittance (e.g., 50%), the irradiation section 50 of the stage 10 is controlled to emit planar light from the above-mentioned opposite surface 51a of the light guide plate 51. In addition, at this time, the irradiation section 50 of the stage 10 is controlled to operate under the same conditions as during inspection, that is, when each component area of the liquid crystal panel 60 is the above-mentioned predetermined transmittance, the wafer W is irradiated with light close to the desired illuminance. Thereby, light is irradiated upward from the mounting surface 40a of the stage 10. And, the illuminance of the light irradiated from a certain unit sensor area of the mounting surface 40a is measured by the illuminance sensor 32. Thereafter, the movement of the stage 10 caused by the X-direction moving unit 21 and the Y-direction moving unit 22 and the measurement of the illuminance caused by the illuminance sensor 32 are repeated. As a result, the illuminance of light from each unit sensor area is measured for all parts of the mounting surface 40a corresponding to at least the imaging element forming area of the wafer W. Based on the measurement result, the control unit 13 obtains the in-plane distribution of the illuminance of light irradiated via the mounting surface 40a.

Next, the control unit 13 determines the transmittance of each element region of the liquid crystal panel 60. Specifically, the control unit 13 determines the transmittance of each element region of the liquid crystal panel 60 so that the problem of in-plane uniformity of the in-plane distribution of the obtained light illumination is eliminated or alleviated, that is, the in-plane distribution of the illumination of the light irradiated through the mounting surface 40a becomes in-plane uniform.

After the transmittance of each element region of the liquid crystal panel 60 changes to the determined value, the illumination sensor 32 may be used to perform measurement again to obtain the in-plane distribution of the illumination of the light irradiated through the mounting surface 40a. Furthermore, if the obtained result does not become the desired result, the determined transmittance of each element region of the liquid crystal panel 60 may be adjusted based on the obtained result. The acquisition of the in-plane distribution of the illumination of the light irradiated through the mounting surface 40a and the adjustment of the transmittance of the liquid crystal panel 60 may be repeated until the desired in-plane distribution is obtained.

[Inspection Process Example 1] Next, an example of inspection processing of a wafer W using the probe tester 1 is described. In the following description, it is assumed that one imaging element D is inspected in one inspection. However, multiple imaging elements D may be inspected at one time in one inspection using the probe tester 1. In addition, the following inspection processing is performed under the control of the control unit 13.

For example, first, the wafer W is taken out of the FOUP of the loader 3 and transported into the storage chamber 2. Then, the wafer W is placed on the placement surface 40a of the pedestal 10 in such a manner that the inner surface of the imaging element D formed on the wafer W faces the pedestal 10 and the inner surface of the wafer W abuts against the pedestal 10.

Next, the stage 10 is moved by a moving mechanism including the X-direction moving unit 21, etc., so that the probe 11a disposed above the stage 10 comes into contact with the electrode E of the imaging element D of the inspection object.

Then, light is irradiated from the irradiation unit 50 under predetermined conditions. Thus, for example, all LEDs of the light source unit 52 are turned on, and light is incident from each LED to the side surface of the light guide plate 51. The incident light is reflected and diffused toward the mounting surface 40 inside the light guide plate 51, and is emitted in a planar shape from the opposite surface 51a of the light guide plate 51 that is opposite to the wafer W.

The light emitted in a planar shape from the above-mentioned opposite surface 51a passes through the liquid crystal panel 60 which has been adjusted to the determined transmittance in the illumination distribution acquisition/transmittance determination processing, diffuses in the top plate 40 and simultaneously penetrates through the top plate 40, and is incident on the wafer W, that is, on the photographic element D of the inspection object.

While the light is being irradiated, an inspection signal is input to the probe 11a. In this way, the imaging element D is inspected.

In the above inspection, the temperature of the wafer W is measured by a temperature measuring mechanism (not shown), and the temperature adjustment unit (not shown) provided on the base 70 is controlled based on the result, and the temperature of the wafer W is adjusted to a desired value to adjust the temperature of the imaging element D to a desired value. Afterwards, the same processing as above is repeated until the inspection of all imaging elements D is completed.

[Main effects of the present embodiment] As described above, in the present embodiment, the probe 1 has a pedestal 10 that supports the wafer W in a shape that is opposite to the inner surface of the internal illumination type imaging element D, and the pedestal 10 has: a transparent mounting surface 40a for mounting the wafer W; and an irradiation unit 50 that is arranged below the mounting surface 40a and irradiates light toward the wafer W mounted on the mounting surface 40a. In addition, the irradiation unit 50 has: a light guide plate 51 that has an object surface 51a that is opposite to the wafer W with the mounting surface 40a in between; and a light source unit 52 that is arranged in an area on the lateral outer side of the light guide plate 51 and emits light toward the side end surface of the light guide plate 51. Furthermore, the light guide plate 51 emits the light emitted from the light source unit 52 and incident from the side end surface of the light guide plate 51 in a planar manner from the opposite surface 51a toward the mounting surface 40a. In addition, the pedestal 10 further has a liquid crystal panel 60 that transmits the light from the opposite surface 51a of the light guide plate 51 toward the wafer W mounted on the mounting surface 40a. The liquid crystal panel 60 is structured to be divided into a plurality of element regions, and the transmittance can be changed for each element region. Therefore, in the present embodiment, the in-plane distribution of the illumination of the light from the mounting surface 40a is obtained, and based on the obtained result, the transmittance in the liquid crystal panel 60 is adjusted for each element region, thereby making the in-plane distribution of the illumination of the light from the mounting surface 40a uniform in the plane, specifically, making the in-plane distribution of the illumination of the light from the mounting surface 40a uniform in the plane at a desired illumination. That is, according to the present embodiment, when the side-incident type irradiation unit 50 is used in the inspection of the internal surface illumination type imaging element D, the wafer W can be irradiated with in-plane uniform planar light, specifically, the wafer W can be irradiated with in-plane uniform planar light at a desired intensity. When inspecting the imaging element D formed on the wafer W, if the wafer W is irradiated with uniform planar light at a desired intensity, the intensity of the light irradiating the imaging element D can be suppressed from deviating from the desired intensity for each imaging element D. As a result, each imaging element D can be inspected correctly.

In addition, in the present embodiment, the side-incident type irradiation unit 50 is used, and the light source unit 52 of the irradiation unit 50 does not overlap with the light guide plate 51 in a plan view. Therefore, even if a heater is provided on the base 70, the light source unit 52 (specifically, the LED included in the light source unit 52) is unlikely to be affected by the heat generated by the heater.

Furthermore, in the configuration of the probe 1 according to the present embodiment, the intensity of light irradiation on the imaging element D can be roughly adjusted by the power supplied to the light source unit 52 (specifically, the current supplied to the LED of the light source unit 52), and finely adjusted by the light transmittance of the liquid crystal panel 60. Therefore, according to the present embodiment, the intensity of light irradiation on the imaging element D can be adjusted in a wide range (e.g., 0.01 lx to 10000 lx) and with high resolution (e.g., 0.1%).

In addition, when the intensity of light irradiation to the imaging element D is adjusted only by the current supplied to the LED of the light source unit 52, it is difficult to make the in-plane distribution of the illumination of the light from the mounting surface 40a uniform within the plane, and multiple power supplies are required to enable adjustment with a wide range and high resolution. In contrast, in the method related to the present embodiment that also utilizes the light transmittance of the above-mentioned liquid crystal panel 60, multiple power supplies are not required in order to enable adjustment of the intensity of light irradiation to the imaging element D with a wide range and high resolution, and thus there is an advantage in terms of cost.

[Other examples of inspection processing] Next, other examples of inspection processing of wafer W using the probe tester 1 are described. In addition, the description of the same parts as the above-mentioned example 1 of the inspection processing is omitted. In addition, in the following description, it is assumed that one imaging element D is inspected in one inspection. However, it is also possible to inspect multiple imaging elements D at one time in one inspection using the probe tester 1. In addition, the following inspection processing is performed under the control of the control unit 13.

For example, similarly to Example 1 of the inspection process, the wafer W is mounted on the mounting surface 40a of the stage 10, and then the probe 11a is brought into contact with the electrode E of the imaging device D as the inspection object.

Next, similarly to Example 1 of the inspection process, light is irradiated from the irradiation unit 50 under predetermined conditions. Thereby, light is emitted in a planar manner from the opposite surface 51a of the light guide plate 51 that is opposite to the wafer W. However, unlike Example 1 of the inspection process, the transmittance of the liquid crystal panel 60 is adjusted so that only specific component areas among the multiple component areas of the liquid crystal panel 60 allow light to pass through. Specifically, only the component area corresponding to the photographic element D of the inspection object in the liquid crystal panel 60 is adjusted to the transmittance determined in the illumination distribution acquisition/transmittance determination process, and the transmittance of the other component areas is set to 0%, that is, the other component areas are set to a light-shielding state. Therefore, among the light emitted planarly from the above-mentioned facing surface 51a, the light that passes through the liquid crystal panel 60 and the top plate 40 is only the light that enters the element area corresponding to the inspection object imaging element D in the liquid crystal panel 60. Therefore, the light can be irradiated to the wafer W only from the area corresponding to the inspection object imaging element D in the mounting surface 40a. That is, the inspection object imaging element D in the wafer W can be partially irradiated with light.

While the light is being irradiated, an inspection signal is input to the probe 11a. In this way, the imaging element D is inspected.

As described above, according to the probe device 1, it is also possible to partially irradiate light only to the imaging element D of the inspection object in the wafer W.

[Other examples of liquid crystal panels] FIG8 is a partially enlarged cross-sectional view of another example of a liquid crystal panel. The liquid crystal panel 60A of FIG8 is different from the liquid crystal panel 60 of FIG7. It has a filter substrate (an example of a filter component) 100 between the glass substrate 62 and the liquid crystal layer 61. The filter substrate 100 is formed in a form that allows a plurality of filters F1, F2, and F3 that allow different wavelengths to pass through to correspond to the element area. For example, the filter F1 only allows the red (R) wavelength to pass through, the filter F2 only allows the green (G) wavelength to pass through, and the filter F3 only allows the blue (B) wavelength to pass through.

By using this liquid crystal panel 60A, it is possible to irradiate the imaging element D with any of a plurality of mutually different wavelengths of light using a single light source, instead of using a plurality of light sources that emit light of mutually different wavelengths.

(Variation) FIG. 9 is a diagram showing another example of the position of the liquid crystal panel 60 in the pedestal. In the above example, the liquid crystal panel 60 is provided below the top plate 40 that functions as a diffusion plate. Alternatively, as shown in FIG. 9 , the liquid crystal panel 60 may be provided above the diffusion plate 110 in the pedestal 10A. In this case, for example, the upper surface 60a of the liquid crystal panel 60 becomes a mounting surface for mounting the wafer W. However, by providing the liquid crystal panel 60 below the top plate 40 that functions as a diffusion plate, it is possible to further reduce the situation where the gap between the element areas of the liquid crystal panel 60 affects the light irradiated to the imaging element D and the inspection result.

In addition, the diffusion plate may be omitted from the base.

The embodiments disclosed herein are exemplary in all respects and are not intended to be limiting. The embodiments described above may be omitted, replaced, or modified in various ways without departing from the scope of the patent application, the appended notes, and the gist thereof. For example, the constituent elements of the embodiments described above may be combined arbitrarily.

In addition, the effects described in this specification are for illustration or example only and are not intended to be limiting. That is, the technology related to this disclosure can achieve other effects that can be understood by a person of ordinary skill in the art to which this invention belongs, together with or in place of the above effects.

In addition, the following structures also belong to the technical scope of the present disclosure. (1) An inspection device for inspecting an inspection object element; The inspection object element is an internal illumination type imaging element that allows light to enter from the inner surface, and is formed on the inspection object, and the inner surface is a surface opposite to a side provided with a wiring layer; The inspection device is provided with a mounting table that supports the inspection object in a shape opposite to the inner surface of the imaging element; The mounting table has: A transparent mounting surface for mounting the inspection object; and An irradiation unit is arranged below the mounting surface and irradiates light toward the inspection object mounted on the mounting surface; The irradiation unit has: A light guide plate having an opposing surface that is opposite to the inspection object with the mounting surface in between; and The light source portion is disposed in an area outside the side of the light guide plate and emits light toward the side end surface of the light guide plate; The light guide plate causes the light emitted from the light source portion and incident from the side end surface of the light guide plate to be emitted from the opposite surface toward the mounting surface; The mounting table further has an optical component, which allows the light from the opposite surface of the light guide plate to pass through the inspection object mounted on the mounting surface; The optical component is configured to be divided into a plurality of regions and can change the transmittance for each of the regions. (2) The inspection device as described in (1) above, wherein the optical component is a liquid crystal panel. (3) The inspection device as described in (2) above, wherein the liquid crystal panel has a plurality of filters that allow different wavelengths to pass through in a shape corresponding to the region. (4) The inspection device as described in any one of (1) to (3) above further comprises a control unit; the control unit obtains the in-plane distribution of the illumination of the light from the mounting surface and adjusts the transmittance of the optical component according to the obtained result. (5) The inspection device as described in any one of (1) to (4) above further comprises a control unit; the control unit adjusts the transmittance of the optical component in a manner that causes light to pass through only a specific area among the multiple areas. (6) An inspection method for inspecting an inspection object element; The inspection object element is an internal illumination type photographic element that allows light to enter from the inner surface, and is formed on the inspection object, and the inner surface is a surface opposite to a side provided with a wiring layer; The inspection method includes: The process of placing the inspection object on a transparent mounting surface in a state in which the inner surface of the photographic element is opposite to the mounting surface; The process of emitting light toward the side end surface of a light guide plate, emitting light from the opposite surface of the light guide plate opposite to the inspection object, and emitting light from the mounting surface after passing through an optical component that is divided into a plurality of regions and can change the transmittance for each region; The process of obtaining the in-plane distribution of the illumination of the light from the mounting surface; and The process of adjusting the light transmittance of the optical component according to the obtained results.

1: Probe tester 10,10A: Base 40a: Mounting surface 50: Illumination section 51: Light guide plate 51a: Opposite surface 52: Light source section 60,60A: Liquid crystal panel 60a: Top surface D: Internal illumination type imaging element W: Wafer

FIG. 1 is a top view schematically showing the structure of a substrate as an inspection object formed with an internally illuminated imaging element. FIG. 2 is a cross-sectional view schematically showing the structure of the internally illuminated imaging element. FIG. 3 is a perspective view schematically showing the structure of a needle tester as an inspection device related to the present embodiment. FIG. 4 is a front view schematically showing the structure of a needle tester as an inspection device related to the present embodiment. FIG. 5 is a perspective view schematically showing the internal structure of a storage chamber. FIG. 6 is a cross-sectional view schematically showing the structure of a base. FIG. 7 is a partially enlarged cross-sectional view of a liquid crystal panel. FIG. 8 is a partially enlarged cross-sectional view of another example of a liquid crystal panel. FIG. 9 is a view showing another example of the position of a liquid crystal panel in a base.

10: Pedestal

40: Top plate

40a: Loading surface

50: Irradiation section

51: Light guide plate

51a: Opposite side

52: Light source

53: Heat sink

60: LCD panel

70: Base

W: Wafer

Claims (6)

An inspection device is used to inspect an inspection object element; The inspection object element is an internal illumination type photographic element that allows light to enter from the inner surface, and is formed on the inspection object, and the inner surface is a surface opposite to a side provided with a wiring layer; The inspection device is provided with a mounting table that supports the inspection object in a shape opposite to the inner surface of the photographic element; The mounting table has: A transparent mounting surface for mounting the inspection object; and An irradiation unit is arranged below the mounting surface and irradiates light toward the inspection object mounted on the mounting surface; The irradiation unit has: A light guide plate having an opposing surface opposite to the inspection object with the mounting surface in between; and The light source part is located in the area outside the side of the light guide plate, and emits light toward the side end surface of the light guide plate; The light guide plate causes the light emitted from the light source part and incident from the side end surface of the light guide plate to be emitted from the opposite surface toward the mounting surface; The mounting table further has an optical component, and the optical component allows the light from the opposite surface of the light guide plate to pass through the inspection object mounted on the mounting surface; The optical component is configured to be divided into a plurality of areas and can change the transmittance for each of the areas. As for the inspection device of item 1 of the patent application scope, the optical component is a liquid crystal panel. As in the inspection device of item 2 of the patent application, the liquid crystal panel has a plurality of filters corresponding to the shape of the area and allowing different wavelengths to pass through respectively. The inspection device of any one of items 1 to 3 of the patent application scope further comprises a control unit; The control unit obtains the in-plane distribution of the illumination of the light from the mounting surface and adjusts the light transmittance of the optical component according to the obtained result. The inspection device of any one of items 1 to 3 of the patent application scope further comprises a control unit; The control unit adjusts the light transmittance of the optical component in such a way that light only passes through a specific area among the multiple areas. A method for inspecting an inspection object element; The inspection object element is an internal illumination type photographic element that allows light to enter from the inner surface, and is formed on the inspection object, and the inner surface is a surface opposite to a side provided with a wiring layer; The inspection method includes: The process of placing the inspection object on a transparent mounting surface in a state in which the inner surface of the photographic element is opposite to the mounting surface; The process of emitting light toward the side end surface of a light guide plate, emitting light from the opposite surface of the light guide plate opposite to the inspection object, and emitting light from the mounting surface after passing through an optical component that is divided into a plurality of regions and can change the transmittance for each region; The process of obtaining the in-plane distribution of the illumination of the light from the mounting surface; and The process of adjusting the light transmittance of the optical component according to the obtained results.